Chevrolet12

I have a 600 Holley carb and was hoping someone could give me some info on swapping parts around... My problem was the metering block.. I was dripping gas from the boosters and we changed the needles bowls etc... Nothing fixed it. I changed the metering blocks with some from a 770 street avenger and dual inlet bowls and no dripping. Just runs rich I have 65 jets in the primary and 72 secondary. Any suggestions on what blocks I can use... Would 750 blocks help any? Or still be too big? Also if it help any I have a Holley red fuel pump running right about 7psi. Thanks again

rklessdriver

Holley carbs are pretty simple.

If its dripping fuel out the booster you have the float level too high. Fuel level should be at the bottom of the sight plug in the side of the bowl.

The float being too high will also make it rich because your covering up some of the high speed air emulsion holes in the metering block with fuel that should be above fuel level.

Set your floats so that the fuel is at the bottom of the site hole, set your mixture screws at .5 turn to 1.5 turns out from seated. Make sure the throttle blades are closed so that the primary bores transfer slot is square.... if the transition slots are showing too tall the carb will be rich because it thinks your at part throttle and activating the main circuit.
Will

Chevrolet12

Already set float level.. The metering block was the problem and I swapped front and rear with blocks from a 770 and what do you know? No more dripping.. It runs rich. I can turn the idle mixture screws in and the idle clears up. Plugs are black. Question was are these blocks not gonna work with the 600? I know the simple basics of a Holley but I don't know everything about them. I know how to set float level and idle mixture and how to take it apart and rebuild.. That's about it.

Chevrolet12

Basically what I'm asking is should I get a set of billet metering blocks with air bleeds etc would that work? The ones I see say for 4150 and 4160 carbs...

JackDidley

Power valve size ? Old or new. Leaky PV will make it rich.

Chevrolet12

New 6.5. rebuilt carb everything clean. Already know that the metering blocks were the problem to begin with. Are you telling me that the 770 street avenger metering blocks on my 80457 - 2 600cfm carb should work fine?

Chevrolet12

I have been told by a few people that the metering blocks will make it run too rich because the hole sizes in the blocks.. I can get a set of fully adjustable ones but I was wondering if anyone has swapped those on a 600 Holley.. Or if they wouldn't work..

Chevrolet12

When I changed the metering blocks it stopped dripping gas from the boosters.. So that problem was the original metering blocks. Now I think I have a problem with the metering blocks being too much for a 600..

project C4

I really don't think the metering blocks caused the original problem.
you may have taken it apart and when you put it back together the boosters stopped dripping but the metering blocks weren't the problem. I would put it all back together stock with all the mating gasket surfaces perfectly clean and go back with new blue gaskets.

unless you really know what your doing its not a good idea to mix and match parts like that. not saying it will never work, sometimes you get lucky most of time not.

on the billet metering block subject. most of the stuff like that is calibrated for higher level carbs. "i.e" 750 double pumpers

cv67

Try Jeff over at AED he can straighten you out

Chevrolet12

And do you want to say why you don't think the blocks were the problem? Because anything that has been mentioned here already did. Needles bowls float level power valve has been changed.. Had the carb at on 2 engines and a buddy try to figure it out and we've already went through everything that would cause it. Besides the blocks. I changed them and it stopped, you have no reason why you think the blocks weren't the cause.

Chevrolet12

Thank you. I will try aed...

project C4

I is just super rare. it would have to be cracked or broken somewhere. anything can happen though

Chevrolet12

I just know for a fact that it was fixed when I changed the blocks... Rare or not that is the only part that fixed it. I have used holley carbs for years so I know the basics of what should cause flooding.. Thanks for being helpful though

project C4

did you change to a different bowl also ?

Chevrolet12

Did that a while ago no change. We thought there was corrosion and fuel was going past the needle. No change then.

383vett

At this point, just get a new carb. A 600 is too small anyway unless you are after gas mileage.